High-grade wood rosin



Patented May 1929.

v UNITED STATES PATENT 1,715,085 FFICEQ;

HARRY n-msna AND ROY sfnnncocx, or xn vvI Ivnw JERSEY, Assrenon's 'ro nnncunns rownnncorarmw, on wrnmme'ron, DELAWARE, A CORPORATION on DELAWARE.

HIGH-GRADE woon nosrn.

No Drawing. Original application filed fliareh 6, 1926,'Seria.1 Fla 92,890. Divided and this application fll'ed August 18, 1926. Serial No. 130,104.

. Our invention comprises a high grade wood rosin devoid of certain color bodies which are normally present in Wood rosin and wl1ich,it is believed, have neveiubeen hitherto eliminated 5 therefrom, 'althoughtheir presence, for many when used as an ingredient of soap and other products.

The purified high grade wood rosin in ac} cordance with my invention may be difierentiated from comparable high grade gum rosin, for example, by the fact that the purified Wood rosin will be found to have an optical 2 rotation of from about +1 to about as compared with from about to about: 35 for high grade gum rosin and the purified wood rosin will be found to contain from about 0.1% to about 0.5% of gasoline insolu-- bles as compared to from about 2.0% to about I 5.0% of gasoline insolubles contained in high grade gum rosin. V

Wood rosin embodyin our invention is adapted for use in sizing tie higher grades of paper and in the manufacture of the better grades of varnish, and indeed'is so thoroughly purified and refined thatit is adapted for use in the manufacture of high grade rosin soaps and limed varnishes of satisfactory color, as well as for most, if not all, other purposes for which gum rosin is adapted.

- In order that those skilled in the art may produce wood rosin having the qualities and characteristics distinguishing our invention partly purified and refined, we shall describe in detail the process that we have successfully used for its production. a w

A known process of producing wood rosin of a lower gradeyand the process that we preferably, but not necessarily, employ as a preliminary process in the manufacture of our more highly refined rosin, consists in grinding wood and stumps from pine trees, placing the Wood stock in large digesters, passing steam thr'ough the stock and thus drivingoifa considerable quantity of turpem' tine, flooding the stock with gasoline or other from other wood rosin, whether crude or solvent, thereby extracting certain materials, chiefly rosin, pine oil and various color bodies, passing. "the gasoline solution, commonly known as. drop liquor, through suitable evaporator-s, and fractionally removing the gasoline and pine oil. The pine oil produced by the distillation is refined and sold. 'The recovered gasoline is again usedin the proc- BSS.

The recovered rosin is a marketable produet, but is not satisfactory for sizing the h ghest grades of .paper or in making the higher grades of varnish, and therefore must be marketed at a relatively low price.

By means of a preliminary distillation, some of the objectionable coloring, matter may be removed. By distilling under a high vacuum at a temperature of from 475-650 F., preferably 550600 F., and fractionally condensing at temperatures of about 400 F.,- 350 F. and 300 F., three grades of rosin are recoverable, the highest grade being adapted for use in the manufacture of varnish and the 'higher grades of paper. The proportion of high grade rosin that is recoverable by this process, however, issubstantially less than is recoverable by our process, and such rosin is not of a sufiiciently high grade to be adapted for use in the manufacture of high grade rosin soaps and limed v'arnishes of satisiacW-- tory color; nor does such rosinfliav certain characteristics peculiar to the high grade rosin produced by our process, which characteristics will be hereinafter fully set forth. In the practice of our process, the rosin may be first subjected to any, desired distillation process, but such preliminary distillation is unnecessary, and it is preferred to omit it.

Our process comprises the formation of a solution of gasoline, rosin and furfural v (0 1-1 0 its cooling or refrigeration with resultant separation of furfural and coloring bodies, and the recovery of high grade rosin from the remaining solution; The process p inaytbe carried out in a single operation, or in two or more operations. It is convenient and economical to divide the process into two operations, and itwill be so described as a preferred Way of practicing the process. 1 Our process also contemplates, as aminor step, the conversion of the larger part of such minor part of the rosin as is not converted into high grade rosin, and which is of low grade, into medium grade rosin, but such medium grade rosin does not'have the peculiar characteristics of the high grade rosin hereinafter claimed. Our process also contemplates the recovery and re-use of the fur-- Pounds.

Gasoline Rosin 15 Furfural -1 11 line is also carried down. The upper ayer is a. homogeneous solution of gasoline, I'OSlI]. and furfural. Typical compositions of the two layerswould be as follows (ignoring the small roportion of gasoline that scarried 1 y) 28P0unds of g e and-the gasoline v down y the furfural, and'bearing in mind that the amounts ofrosin and'furfural in each layer are only approximate) Furfural 6.75

To the solution (B) resulting fromthe first treatment is now added more furfural, say 11 pounds, giving the following composition f Pounds. Gasoline 85 Rosin 12' Furfural 15.25

To this mixture heat need not be applied, but it should be agitated to obtain a thorough washing, and is then cooled down to about 10 F. in order to secure as complete a separation as possible; the solubility of furfural in gasoline decreasing with decrease of teming (approximate) composition (G) About or low grade rosin.

line and rosin, with a little furfural. Typical (approximate) compositions of the two layers are:

i U ppm" lag/er (E).

Pounds. Gasoline 1' 85 Purified rosinn' '-L 10.5 F urfural 2.125 Lower layer (F).

' Pounds. Dark rosin 1.5

Furfural 13.125

From composition the gasoline and then the furfural are distilled off, leaving a purified, highest grade rosin having the characteristics, hereinafter described, that distinguished the same from-all othcr'heretofore known wood rosins. The recovered gasoline and furfural is then rc-used in the process.

Compositions (C) and (F), being the precipitates of the two describedtreatments, are then (preferably) mixed, giving the follow- Pounds. Dark rosin -Furfural 19.875

The furfural is distilled off, leaving a dark The furfural is re-used in the process.

This low grade rosin may be dissolved in soluble. rosin extracted. The insoluble residue is a very dark, brittle substance, being about 5% of the original rosin (say .75

pounds). From the gasoline-rosin solution, .the gasoline is distilled off, leaving about 3.75 Y I pounds of a medium grade rosin, being about 25% of the original rosin. The recovered gasoline is re-used in the process.

While the above figures show a recovery of 7 0% of the original rosin as high grade rosin, the percentage .of recovery by the practice of the process ranges from to While we have illustrated one way of carrying out the process involving two treatments, in thefirst of which the mixture of gasoline, rosin and furfural is heated to a relatively high temperature and then cooled to a medium temperature, followed by a gravity separation, and in the second of' which the lighter product of the separation is refrigerated, followed by a gravity separation, it should be understood that the process is capable of being carried out, although with less economy of heat, by a single refrigerating-treatment, preferably preceded by heatingto insure a good homogeneous solution, and followed by a gravity separation. It is also feasible, and may be in some cases 'advantageous, to increase the number of Stages in the treatment. That is, there may be a succession of more or less rough separations of the character described, followed by a final separation.

Less advantageously and less economically,

.it is possible to dissolve rosin in gaoline and substituted.

\Vhile we have specified gasoline as the sol- ,vent for the rosin and furfural, it is intended, by specifying that substance, to include operative equivalents, suchas other mineral oil distillates that have not too high a vaporizing temperature. -We have even used the lighter lubricating distillates. A heavy hy; drocarbon product, however, is undesirable, or even impracticable, because of its decomposing action on the rosinin the step of distilling off the hydrocarbons.

The advantage of furfural is that it is capable of entering into solution with the gasoline and of dissolving or absorbing the coloring bodies of the rosin, and'yet can be largely precipitated from the gasoline and most of the rosin without giving up such coloring bodies.

The temperatures at the beginning to a temperature sufficiently high to form a substantially homogeneous solution, say in excess of 100 F. and that the refrigerating temperature at the end shall be below 25 F. Temperatures as high as 115 F. and as low as 10 F., as specified. are

believed to be necessary to secure the best possible solution to start with'and a maximum recovery of thehighest grade rosin, although less nearly perfect results. with respectto quality and quantity, may be secured bydepartures from the above temperatures.

The relative proportion of the constituents specified in the several successive compositions are illustrative merely, and are 'susceptible of considerable variation.

The high grade rosin resulting from the above preferred process, or from the described modifications of the process, and which embodies our invention. has certain definite characteristics by which it is distin v guishable from hitherto known wood rosins, including those which are partly purified. All such hitherto known wood rosins contain color bodies, the .precise nature of which is not known, but which have certain known objectionable effects when used in the manufacture of certain substances, such as rosinsoaps.

If, for example, the ordinary commercialv wood-rosin is. used in, the manufacture of soap, a finished cake of freshly made soap presents a dark green interior, Imthe course of time, usually Within a few weeks, the dark brown color brown exterior and an olive gradually spreads from the surfacezutoward the center of the cake, as maybe seen" by taking a cross-section through the soap. In

other words, the color is not uniform or ho-' mogeneous,,'or if it becomes so after lapse of .sufiicicnt tlme, the color throughout Wlll become a dark brown This dark brown'color,

whether characterizing only the surface or penetrating a greater or lesser distance interlorly, is highly objectionable and unacceptable except where only a low grade soap is desired.

- The most highly purified wood rosins hitherto known are also not adapted to the man ufacture of high grade soap. The initial color of the soap maybe fairly satisfactory,

but the surface .speedily darkens, and this dark color gradually permeates the soap and spreads toward the center, and a cross-section through the soap "exhibits the diflterentialcoloring above described. 1

Undoubtedly, the objections to hitherto known wood rosin soaps arise tains color bodies which react, in the presence of air, with the alkali in the soap, to form from the fact that the rosin used in their manufacture concompounds that effect the pronounced and progressive darkening described.

specified are I largely a matter of choice, although it is desirable that" v the rosin-containingmixture shall be heated When, however, the purlfied rosin embody "ing our invention is utilized in the manufactureof soap, 1t produces soap having a light buff color. in the degree of lightness, dependent on the particular'way in which our process for the urification of the wood rosin is practiced, on

t e other ingredients of'the soap, and on the method of manufacturing the soap but whatever color the soap may be, its color is the same throughout its mass and if there should be any degree of darkening with lapse of time, the change'in color doesnot develop or progress from the surface inwardly, butproceeds uniformly throughout the mass, a cross-section through the soap exhibits at all times a uniform appearance with regard to color. .A wood rosin embodying our invention is, therefore, one devoid of those color bodies which, when the rosin is present in a substance containing an alkali, react, in

the presence of air, with such alkali to produce compounds that progressively darken vthe sulostance. A wood rosin embodyingour invention may be also accurately defined as This color may vary somewhat so that v one which, when employed as an ingredient of soap, produces soap which, when freshly made, or at any given time thereafter, exhibits a substantially uniform or homogeneous color throughout its mass, whether or not there may be any modification of the uniform color With la-pse'of time.

In the case of soap made with high grade gum rosin, a narrow band ofdarker color forms just under the surface. This dark band never extends to the surface of thesoap. This slight band of darker color will also form in soap made with Wood rosin refined by the present process. It does not appear, however, until afterthe soap is aged'for aconsiderable period, say from ten to twelve months. This darkening, it is believed, is caused, in soap made with wood rosin refined by the present process as Well as in soap made with gum rosin, by the gradual drying of the soap, rather than by any color bodies origi-- nally present in the rosin.

This application is a division ofan application filed by us'March 6,1926, Serial No.-

92,890,'for a process of producing high grade wood rosin, which in turn is in part a continuation of an application filed by us June 5,

1925, Serial No. 35,245, for a process of covering high grade wood rosin. I

Having now fully described our invention,

2. A purified high grade wood rosin having an optical rotation of from about +1 to about 10 and substantiallydevoid of those latent color bodies which tend to darken in the presence of air and an alkali and which are removable from wood rosin-by the treat- 7 mcnt thereof with furfural.

In testimony of which invention, I, IIARRY- 1(AISER have hereunto set my hand at Cologne, Germany, on this 2nd day of August, 1926, and I, ROY S. HANcooK. have hereunto set my hand at Kenvil, New J crsey, on this 17th day of July, 1926.

HARRY E., KAISER.

ROY S. HANCOCIC. 

